<!DOCTYPE html>
<html>
<head>
    <meta charset="utf-8">
    <title>Vue 测试实例 - 菜鸟教程(runoob.com)</title>
    <script src="https://cdn.staticfile.org/vue/2.2.2/vue.min.js"></script>
</head>
<body>
<div id="app">
    <div id="counter-event-example">
        <p>{{ total }}</p>
        <button-counter v-on:increment="incrementTotal" @sendmes="fromchild"></button-counter>
        <button-counter v-on:increment="incrementTotal" @sendmes="fromchild"></button-counter>
    </div>
</div>

<script>
    Vue.component('button-counter', {
        template: '<div>' +
            '<button v-on:click="incrementHandler">{{ counter }}</button>' +
            '<input type="text" v-model="childData" @input="changeValue(childData)" />' +
            '</div>',
        data: function () {
            return {
                counter: 0,
                childData: ''
            }
        },
        methods: {
            incrementHandler: function () {
                this.counter += 1
                this.$emit('increment')
            },

            changeValue(val){
                //在函数中使用$emit触发父组件中的自定义事件
                this.$emit('sendmes',val)
            }
        },
    })
    new Vue({
        el: '#counter-event-example',
        data: {
            total: 0
        },
        methods: {
            incrementTotal: function () {
                this.total += 1
            },
            fromchild(val){
                console.log('from child'+val)
            }
        }
    })
</script>
</body>
</html>
